I have a different perspective of an observer's observation conclusions of Saturn's rings - presuming that the observer stands sufficiently far away from Saturn.
Regarding Saturn's debris, if one was on-plane with the moving debris, one wouldn't think that the debris moves in a straight line if one had binocular vision. One would see that the debris was moving in a circular path along the surface of an an imaginary plane that was straight-in-line with the observer's position.
If one was standing off to the side, one would still see debris moving in a circular manner, and one would be able to imagine its circular orbit being along an orbital plane that is angled relative to the observer's position.
When watching someone twirling a stone attached to a string in a circle around his head, I would never perceive the stone to be traveling in a straight line - no matter what the angle of the observation point relative to the orbiting object's orbital plane.
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